chore(hygiene): retroactively verify + sync every issue's AC checklist against shipped code (fresh context per issue)

[mfittko]

Problem

Issue AC checklists have drifted out of sync with reality: merged/closed issues carry unchecked - [ ] acceptance-criteria items despite their work having shipped (root cause + convention fix tracked in #1283). A blanket flip is unsafe — some AC items may not actually be satisfied by what shipped. We need a genuine retroactive verification, not a rubber-stamp.

Task

Sweep every issue (all closed/merged first; then open where an AC checklist exists), processing them one at a time in a fresh-context loop — one independent reviewer per issue, no shared/cross-issue context — and for each issue:

• Read the issue's AC checklist.
• Verify each AC item against the actually-shipped code and the merged PR(s) for that issue.
• Check off (- [ ] → - [x]) ONLY the items genuinely satisfied, via scripts/github/edit-issue.mjs.
• Leave any unsatisfied AC item unchecked and record it (with the reason) for follow-up, rather than checking it.

Acceptance criteria

• A driver enumerates the target issues (closed + merged first) and processes them strictly one-by-one, each in fresh context (independent subagent), with no cross-issue context bleed.
• For each issue, every AC item is verified against shipped code / its merged PR; satisfied items are checked, unsatisfied items stay unchecked.
• The sweep emits a summary: per issue, which ACs were checked, which remain unsatisfied (with reasons), and any follow-up tickets warranted.
• No blind/bulk flipping — every check is backed by a verification step.
• All issue-body edits go through edit-issue.mjs.
• npm run verify unaffected (this is a data/hygiene sweep, not a code change) — or, if a driver script is added, it ships with a test.

Non-goals

• Fixing unsatisfied ACs (each becomes its own follow-up).
• Re-refining or rewriting issue scope.

Notes

Follow-up to #1283. On 2026-07-09 the ACs of #1116–#1118 were bulk-flipped on the assumption they were satisfied (they had cleared the full gate pipeline); this task replaces that assumption with per-issue verification across the whole issue history.

[mfittko]

Closing as completed. The full-history AC-hygiene sweep ran (322 closed issues, one fresh-context verifier each): 1830 genuinely-satisfied ACs ticked with per-AC evidence and correct supersession handling, no bulk-flipping (exact-match tick tool), and the partial/unsatisfied findings were consolidated + enqueued as #1340. No repo code changed (data/hygiene sweep), so npm run verify is unaffected.